【摘要】 利用高功率CW CO₂激光束在细片状石墨加珠光体的灰铸铁表面上进行激光Si合金化的基础研究。基材成分（wt%）为C3.0、Si2.2、Mn1.0、Cr 0.40,其碳当量为3.68。合金粉末为Si75+Fe25（wt%）。研究结果表明即使在合金熔体的冷却速度达到10³K/s 的数量级,Si的平均含量为5.37%的条件下,仍然未能抑制在表面 Si 合金化层中出现石墨化倾向。新的表面合金中不存在r-Fe 和 Fe₃C。利用共晶度对 Si 含量的敏感性,直观地证实了在合金熔池的固—液界面附近确实存在传质现象。更多还原

【Abstract】 Laser Silicon alloying on grey cast iron was studied,with thehelp of high CW CO laser.This cast iron consisted of small plate graphiteand pearlite,its chemical composition was C 3.0,Si 2.2,Mn 1.0 Cr0.40（%）and its carbon equivalent was 3.68.The alloying powder was Si 75+Fe 25.The findings showed that,although the cooling speed for the iron melt was ashigh as the order of 10³K/s and its average Si content was 5.37%,the tendencyfor the surface alloying zone to graphitize still existed.The γ-Fe and Fe₃ Cphases did not exist in this new surface alloy.On the other hand,it wasdirectly confirmed that the mass transfer phenomenon existed indeed in thevicinity of solid/liquid interface,by the sensibility of the eutectic degree tosilicon content.更多还原